Tag : mysql

Used in the projectExpress, usedexpress-myconnectionMiddleware creates connection pools with a limit of 10 connections. In the process of operation, if the number of links exceeds the limit, it will be blocked directly. No matter waiting for Takuya to make new inquiries, it will not report an error and obtain links again.The reason for this problem ..

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Node mysqlconnection.query(‘select * from table where tel=?’ ,[tel],function(){}), what if tel has multiple values? connection.query(‘select * from table where age=? and tel in (? );’ ,[20, [1, 2, 3]],fun..

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Logic of the program: The program generates a lottery code in advance and stores it in mysql. When a user comes, he finds an unused lottery code and sets the lottery code as already used Question:When a large number of users concurrently request, most users return the same lottery code. The reason is probably this ..

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The specific implementation is to query the number of products in the product table for today, seven days and thirty days, and the specific sql statement has been written select sum(inputer as productNum) from `product` where to_days(`createdAt`)= to_days(now()); But in knex.js, I am writing this wrong at all. return knex(‘product’) .where({ inputer: user, deletedAt: null ..

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Enter the account number and password, compare them with mysql, and go to the home page if correct.database.js: var mysql = require(‘mysql’); var config = require(‘../config/config’); var pool = mysql.createPool(config.mysql_dev); var query=function(sql,callback){ pool.getConnection(function(err,conn){ If(err) console.log(“POOL == > “plus err); else{ conn.query(sql,function(qerr,vals,fields){ //Release connection conn.release(); //Event Driven Callback callback(qerr,vals,fields); }); bracket }); }; module.exports=query; index.js: router.post(‘/login’,function(req,res){ ..

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How do you generate globally unique and increasing serial numbers under the application server cluster? If not, one solution is based on machine code differentiation. It is to automatically or manually assign a globally unique machine ID to each server and use the method of “machine ID plus local unique self-increment”. But this does not ..

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